1. Field of the Invention
The present invention relates to a discharge head; and more particularly to a discharge head for a vertically suspended pump type.
2. Brief Description of Related Art
By way of example, FIG. 1A shows a known vertically suspended pump type and includes reference designations of various parts and components that make up the same. Vertically suspended pumps are known in the art which operate in an upright position and employ a bowl assembly including a rotary impeller submerged in a body of liquid or fluid to be pumped. By way of further example, the reader is also referred to U.S. Pat. No. 8,226,352, which discloses a discharge head for configuring in such a vertically suspended pump type, which is assigned to the assignee of the present invention, and hereby incorporated by reference in its entirety.
In operation, discharge heads of vertical pumps are often subjected to high piping forces from expanding pipe joints at the connection between the piping and pump discharge flange. These expanding pipe joints are designed to be flexible and are typically constructed of rubber elements. The high piping forces which occur in the direction perpendicular to the face of the pump discharge flange are the result of elastic expansion of the expanding pipe joint elements along their centerline axis when pressurized. When flexible pipe joints are used, these forces are approximately equal to the discharge pressure times the projected area of the inside diameter of the joint. For example, a 36-inch diameter expanding pipe joint pressurized to 100 psig produces a piping force equal to 101,736 lbf acting horizontally against the pump discharge head.
High piping forces applied against standard discharge head designs cause material deflection of the discharge head which in turn causes misalignment of the stationary bearings mounted in the discharge head from the rotating shaft of the pump. This internal pump misalignment causes high mechanical vibration and contact wear between the bearings and bearing journals on the shaft. As a result, pump life is shortened.
There is a need in the industry for a discharge head design that reduces the undesirable effects from high piping forces, including misalignment of the bearings mounted in the discharge head from the rotating shaft of the pump and high mechanical vibration and contact wear between the bearings and bearing journals on the shaft.